Carly Rae Jepsen, Renee Zellweger and Julianne Hough: Hottest Star Sightings of the Day (PHOTOS)

Carly's Duet with Justin
Carly Rae and Justin Bieber sing 'Beautiful.'
Julianne on Ryan
Julianne Hough says she's gained 20 pounds since dating Ryan Seacrest.
From talk show duties to red carpet affairs, there was plenty of star action around the world in the last 24 hours.

On Thursday night, Carly Rae Jepsen paid a visit to the Late Show with David Letterman, serving as the episode’s musical guest.

The 26-year-old Canadian singer sparkled in a black-and-grey blazer, which draped over a leopard print top and bejeweled skirt.

Elsewhere in the Big Apple, Renee Zellwegger turned heads in a Carolina Herrerra dress at a fashion event at Cipriani Wall Street. The 43-year-old actress mingled with fellow fashion icon Sarah Jessica Parker, who donned a colorful L’Wren Scott number.

On the West Coast, Julianne Hough stunned head-to-toe in blue at the Samsung Galaxy Note II launch party in L.A. The Rock of Ages star celebrated the new product with a slew of other famous faces that included Liam Hemsworth, Rosie Huntington-Whiteley and Octavia Spencer.

Off the red carpet, airport fashion was in full force, as Bar Refaeli and Kelly Osbournewere spotted at Berlin-Tegel International and Heathrow, respectively.

For the hottest celebrity sightings of the day, check out the latest edition of Celeb Snaps, above.

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